If you’ve ever wanted to learn more about what lies beneath the surface of New York City’s waterways, you can find out Saturday at Submerge, a free, day-long marine science festival held at Pier 26 at Hudson River Park.

In partnership with the New York Hall of Science, the festival, now in its second year, combines hands-on learning and interactive demonstrations to bring New Yorkers closer to the water that surrounds them. Organizations from the Bronx River Alliance to Gotham Whale will set up research stations to teach viewers about topics ranging from marine robotics to oyster filtration. Expect close-ups of river wildlife like oysters, horseshoe crabs, seahorses and more.

The all-ages event includes kid-friendly activities, such as marine-themed arts ‘n crafts and a Discovery Station where they can “meet” live animals in an interactive touch tank.